Amphibious vehicle drive train

ABSTRACT

A drive train for an amphibious vehicle provided with a propellor disengaging mechanism aft of the transfer case, thus allowing the output drive shafts to be continuously driven at all times. The drive train includes a motor attached to a transmission which is attached to a transfer case. The attachments are accomplished by rotatably coupled drive shafts. The drive train transfers rotational movement from the motor to the transmission, then to a transfer case where it is output to the various drive shafts enabling the vehicle to be propelled on land and in water.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application is a continuation of U.S. applicationSer. No. 09/596,496, entitled “Amphibious Vehicle Drive Train”, filedJun. 19, 2000, now U.S. Pat. No. 6,575,796.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] Not Applicable.

BACKGROUND OF THE INVENTION

[0003] The present invention relates to a drive train for an amphibiousvehicle and, more particularly, to a drive train where all of the driveshafts are continuously rotating and a propellor engaging mechanismexists aft of the transfer case for engaging and disengaging thepropellor.

[0004] Amphibious vehicles present unique design challenges. Unlike carsand trucks, which are designed specifically to be driven on the land,and boats, which are designed specifically to be driven in water,amphibious vehicles must be designed to handle both tasks equally well.When driven on land, the body of an amphibious vehicle must drive likean ordinary road vehicle. On the other hand, when the amphibious vehicleis propelled in water, the vehicle must have the ability to maneuverlike a boat. Therefore, the vehicle has to be provided with a propulsionsystem which drives both on land and in water.

[0005] In the past, a dual propulsion system was achieved by using aswitching mechanism on the transfer case to allow the drive system to beused either for land or water. The switch allowed the propulsion systemto drive the boat on land as well as in water, but had to be switchedbetween the two. This type of arrangement needed a complex transfer caseand switching mechanism to allow for transformation between the two. Onesuch complex transfer case can be found in U.S. Pat. No. 5,562,066.

[0006] Another dual propulsion system was achieved by adding a small,two-speed transfer case between the primary transfer case and thetransmission. This allowed the propellor to be driven off one shaft andthe other shaft run to a second transfer case where it was then directedto the driving wheels. However, due to the short distance availablebetween the rear of the transmission and the front of the main transfercase, it is difficult, if not impossible, to place any new or largercomponents in this limited space. The additional gearbox was located inthis region of limited space and thus two very short drive shafts wereprovided. This configuration is very cramped and does not allow use ofthe very large truck-style automatic transmissions that are needed totransfer power of the large engines that are employed. Morespecifically, due to limited area between the transfer case and theautomatic transmission, there is not enough room for the additional gearbox and the large truck-style automatic transmissions and thus, thepresent invention arose.

BRIEF SUMMARY OF THE INVENTION

[0007] Accordingly, it is an object of this invention to provide asimple amphibious propulsion system which operates both amphibious andground drives wherein a simple transfer case can be utilized without anycomplex switch to select between land use or marine use.

[0008] Another object of this invention is to provide an amphibiouspropulsion system consisting of only one transfer case whose outputscontinuously drive both the land and marine functions.

[0009] Another object of this invention is to provide a disengagingmechanism for the propellor located aft of the transfer case to allowthe propellor shaft to be disengaged when not in use.

[0010] A still further object of this invention is to position thecomponents of the drive train rearwardly to add further balance to thevehicle.

[0011] Accordingly, the present invention provides for a simpleamphibious propulsion system including a drive train which is capable ofpropelling the vehicle on land and in water. The drive train comprises amotor rotatably coupled to a transmission via a drive shaft. Thetransmission is then rotatably coupled to a transfer case using anotherdrive shaft. Each output drive shaft of the transfer case continuouslyrun while the vehicle is in operation. Although the drive shafts arecontinuously rotating, an engaging mechanism for the propellor islocated aft of the transfer case and before a gearbox to disengage thepropellor when not in use.

[0012] Further objects, features, and advantages of the presentinvention over the prior art will become apparent from the detaileddescription of the drawings which follows, when considered with theattached figures.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

[0013] The objects and features of the invention noted above areexplained in more detail with reference to the preferred embodimentsillustrated in the attached drawing figures, in which like referencenumerals denote like elements, and in which:

[0014]FIG. 1 is a side elevation view of an amphibious vehicle, partsbroken away and in cross section to show the drive train of the presentinvention;

[0015]FIG. 2 is an enlarged side elevation view of the drive train ofFIG. 1 removed from the amphibious vehicle;

[0016]FIG. 3 is a top plan view of an amphibious vehicle of FIG. 1,parts broken away and in cross section to show the drive train of thepresent invention;

[0017]FIG. 4 is an enlarged top plan view of the drive train of FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION

[0018] Referring now to the drawings in more detail and initially toFIGS. 1 and 3, numeral 10 generally designates an amphibious vehicle.The amphibious vehicle 10 has a body 12 constructed so that the vehicle10 has the ability to operate on land and in water. The body 12 has amotor 14 attached to the body 12 in a manner well-known in the art.

[0019] The motor is connected to a transmission 18 by a drive shaft 16.The transmission 18 is rotatably coupled to a transfer case 22, by adrive shaft 20. The transfer case is attached to the body and isconstructed in a manner well-known in the art. The transfer case 22 hasmultiple outputs which operate both the land and marine drives.

[0020] The body 12 has a set of front and rear wheels, 28 and 34respectively. The front wheels 28 are rotatably coupled to a front wheeldrive shaft 24 in a manner well-known in the art. The rear wheels 34 arerotatably coupled to a rear wheel drive shaft 30 in a manner well-knownin the art. The front and rear wheel drive shafts, 24 and 30 are outputsfrom the transfer case. The transfer case 22 is also rotatably coupledto a gearbox 38 via drive shaft 36. The gearbox drives a propellorsystem 39. The propellor system 39 consists of a first propellor driveshaft 40, a second propellor drive shaft 42, and a propellor 44.

[0021]FIGS. 2 and 4 are enlarged views of a drive train 15. The drivetrain 15 includes the transfer case 22 and a disengaging assembly 48.The transfer case 22 receives the output drive shaft 20 from thetransmission. The transfer case has continuously rotating output shafts24, 30, and 36. The front wheel drive shaft 24 is rotatably coupled tothe front wheels in a manner well-known in the art. The rear wheel driveshaft 30 is rotatably coupled to the rear wheels in a manner well-knownin the art. The final output drive shaft 36 is rotatably coupled to adisengaging assembly 48 and used to drive the propellor system 39. Bylocating the disengaging assembly 48 aft of the transfer case, all driveshafts are allowed to run continuously, but the ability to disconnectthe propellor system 39 still exists.

[0022] The disengaging assembly 48 consists of a cable pull 46, a pivotpoint 50, a cable attach lever 56, a gear collar 54, and a coupler 52.The disengaging assembly 48 attached to the coupler 52 is the input tothe propellor gearbox 38. The gearbox 38 is a speed increasing type.More specifically, it speeds up propellor 44 in a manner such that thespeed of the vehicle 10 in water is comparable to the speed the vehicle10 would be traveling on land with the rotation of the wheels. Thisallows the vehicle 10 to move from water to land at the same speedallowing a smooth transition for egress. The gearbox 38 is constructedin a manner well-known in the art such that the rotational speed offirst propellor shaft 40 and thus propellor 44 is greater than therotational speed of shaft 36. The gear ratio in the gearbox 38 isconstructed such that the vehicle travels through the water atapproximately the same speed it would travel over land, thus resultingin the smooth transition from water to land. The output from the gearbox38 is the first propellor drive shaft 40, a part of the propellor system39. The propellor system is seen in FIGS. 1 and 3. This assembly allowsthe propellor 44 to be disengaged while the output drive 36 to thepropellor system is still rotating.

[0023] In operation, the amphibious drive system 15 derives its powerfrom a motor 14. The motor 14 drives the transmission via drive shaft16. The transmission is then connected to the transfer case 22 by driveshaft 20. The transfer case has multiple output drive shafts whichcontinuously rotate. Drive shafts 24 and 30 drive the front and rearwheels 28 and 34, respectively. Drive shaft 36 is rotatably coupled todisconnect assembly 48 and drives the gearbox 38. The disconnectassembly 48 can be selectively engaged or disengaged to the propellorgearbox 38 in the manner described below.

[0024] To engage the propellor 44, the vehicle 10 must be at a completestop. The T-handle cable 46 is then pulled moving the cable attach lever56. The cable attach lever 56 moves about the pivot point 50, which isfixed at a bracket 58. The cable attach lever is a J-shaped lever whichis attached to the gear collar 54. The vehicle 10 is then allowed toroll forward allowing the drive shaft 36 to rotate at the proper speedand align the teeth for proper engagement. The gear and splinecombination is a connection manner well-known in the art. Once alignedand with pressure applied, the gear collar 54 slips into position andthe gearbox 38 is then connected to the drive shaft 36. The firstpropellor drive shaft 40 on the gear box then transmits power to thepropellor drive system 39. The disengaging assembly 48 is located aft ofthe transfer case, but in front of the gearbox 38.

[0025] The propellor system 39 can be disengaged from the gearbox 38 bypushing the T-handle attached to cable 46 back to its original position.When the T-handle cable 46 is pushed, the cable attach lever 56 movesthe gear collar 54 about a pivot point 50. This movement disengages thegear collar 54 from the coupler 52 attached to the gearbox 38. When thegear collar 54 is disengaged from the coupler 52 the propellor 44 ceasesto rotate.

[0026] From the foregoing, it will be seen that this invention is onewell-adapted to attain all ends and objects hereinabove set forthtogether with the other advantages which are obvious and which areinherent to the structure. It will be understood that certain featuresand subcombinations are of utility and may be employed without referenceto other features and subcombinations. This is contemplated by and iswithin the scope of the claims.

[0027] Since many possible embodiments may be made of the inventionwithout departing from the scope thereof, it is to be understood thatall matter herein set forth or shown in the accompanying drawings is tobe interpreted as illustrative of applications of the principles of thisinvention, and not in a limiting sense.

What is claimed is:
 1. A drive train for an amphibious vehicle havingwheels capable of propelling the vehicle on land and a propeller capableof propelling the vehicle in water, the drive train comprising: a motorproviding a rotary output; a transfer case selectively rotatably coupledwith the motor and having at least one wheel drive output and apropeller drive output, wherein the propellor drive output is drivendirectly from inside the transfer case; and an engaging mechanismcoupled with the motor and selectively movable by a vehicle operatorbetween an engaged position and a disengaged position, wherein the motorrotates the propeller when the engaging mechanism is in the engagedposition and wherein the motor does not rotate the propeller when theengaging mechanism is in the disengaged position.
 2. The drive train ofclaim 1, wherein the engaging mechanism is located outside the transfercase.
 3. The drive train of claim 2, wherein the engaging mechanism islocated between the transfer case and the propeller.
 4. The drive trainof claim 3, further including a first drive shaft intermediate andcoupled with the motor and the transfer case, a second drive shaftintermediate and coupled with the propeller drive output and theengaging mechanism and a propellor drive shaft extending from theengaging mechanism for selectively rotating or not rotating thepropellor.
 5. The drive train of claim 4, wherein the propellor driveoutput from the transfer case is continuously rotating when the firstdrive shaft is rotating.
 6. The drive train of claim 5, furtherincluding a transmission coupled with the motor intermediate the motorand the transfer case, wherein the first drive shaft is intermediate andcoupled with the transmission and the transfer case and wherein thetransmission is operable by the vehicle operator to selectively coupleand uncouple the first drive shaft with the rotary output of the motor.7. The drive train of claim 6, further including a third drive shaftintermediate and coupled with the motor and the transmission, wherebythe transmission is spaced apart from the motor via the third driveshaft.
 8. The drive train of claim 1, further including a third driveoutput from the transfer case for driving a second set of wheels.
 9. Thedrive train of claim 1, further including a speed increasing gear boxhaving a rotary output which is faster than a rotary input, wherein thegear box is intermediate the transfer case and the propellor.
 10. Adrive train for an amphibious vehicle having wheels capable ofpropelling the vehicle on land and a propellor capable of propelling thevehicle in water, the drive train comprising: a motor; a first driveshaft coupled with the motor; a transfer case coupled with the firstdrive shaft opposite the motor and having at least one wheel driveoutput and a propellor drive output, wherein the propellor drive outputis driven directly from within the transfer case and wherein the firstdrive shaft provides a drive input to the transfer case; and an engagingmechanism located between the transfer case and the propellor, theengaging mechanism allowing a vehicle operator to selectively engage anddisengage the propellor from the propellor drive output.
 11. The drivetrain of claim 10, wherein the first drive shaft is selectively coupledwith the motor via a transmission.
 12. The drive train of claim 11,wherein the wheel drive output and the propellor drive output rotatewhen the first drive shaft rotates.
 13. The drive train of claim 12,wherein the transfer case further includes a second wheel drive output.14. The drive train of claim 10, further including a second drive shaftintermediate and coupled with the propellor drive output and theengaging mechanism, wherein the first drive shaft is selectively coupledwith the motor via a transmission.
 15. The drive train of claim 14,wherein the transmission is selectively coupled with the motor via athird drive shaft, whereby the transmission is spaced apart from themotor via the third drive shaft.
 16. A drive train for an amphibiousvehicle having wheels capable of propelling the vehicle on land and apropellor capable of propelling the vehicle in water, the drive traincomprising: a motor; a first drive shaft coupled on one end with themotor; a transmission coupled with an end of the first drive shaftopposite the motor; a second drive shaft coupled on one end with thetransmission; a transfer case coupled with an end of the second driveshaft opposite the transmission and having at least one wheel driveoutput and a propellor drive output; a third drive shaft coupled on oneend with the propellor drive output of the transfer case for rotatingthe propellor; and an engaging mechanism located between thetransmission and the propellor, the engaging mechanism allowing avehicle operator to selectively engage and disengage the propellor fromthe motor.
 17. The drive train of claim 16, wherein the propellor driveoutput is driven directly from within the transfer case and wherein thesecond drive shaft provides a drive input to the transfer case.
 18. Thedrive train of claim 16, wherein the engaging mechanism allows a vehicleoperator to selectively engage and disengage the propellor from thepropellor drive output.
 19. The drive train of claim 16, wherein theengaging mechanism is located between the transfer case and thepropellor.
 20. The drive train of claim 16, further including a speedincreasing gear box having a rotary output which is faster than a rotaryinput, wherein the gear box is intermediate the transfer case and thepropellor.